The present invention pertains to a distributed information backup system.
An enormous collection of data is required to carry out most administrative tasks in a technologically complex environment. In practice, such data originate in a large number of geographically dispersed locations. As such, many data base applications systems achieve advantages by storing the collection of data in a central data base. Through centralized storage, the efforts required to gather and administer the data, i.e. to update the data base, are greatly simplified and reduced. For these reasons, "main-frame" computer systems which store and provide access to enormous central data bases have been developed.
The data stored in such central data bases are often accessed by users who are located at many widely dispersed geographic locations. Access to the data is often critical for specific jobs being performed in the "field", i.e. many jobs simply cannot be carried out if the data in the central data base is not accessible to the geographically dispersed users. The central data base may be inaccessible for a variety of reasons, such as, hardware maintenance, data base updating, equipment failure and/or a failure in data communications between a user and the central data base.
To ensure data access, most data base systems provide a backup capability. In one typical system in the art, this backup is provided by duplicating the central data base itself. Alternatively, in other well-known systems in the art, backup is provided by duplicating the computer and/or communications facilities or by combinations of these two methods. Unfortunately, providing backup capabilities is expensive because of the extra hardware and software required for its implementation.
In other systems in the art, a central data base is accessed by users through one or more "front-end" processors which serve as a partial backup capability. These "front-end" processors only contain a small portion of the data that resides in the central data base. Thus, even if a user could access the "front-end" processors when the central data base was inaccessible, the data accessed by the "front-end" processor alone is minimal. This implementation is expensive and it is still vulnerable to failure in data communications.
Thus, a need exists for a reliable, inexpensive data base backup system that provides data accessibility when the centralized data base is inaccessible and when the communication link between users and the centralized data base is not operating properly.